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海龙类前肢化石标本(YIGM SPC V 0832-2)采自于云南省罗平县新寨一带中三叠统安尼阶(Pelsonian亚阶)关岭组二段顶部.其不仅为海龙类在罗平生物群中的首次发现,而且为长颈型海龙的最早记录.该海龙类新材料虽然保存不全,但是仍具有一些独特的特征:桡骨远端两侧边缘平行;尺骨远端扩展;11个硬骨化腕骨;第三掌骨近端内侧缘发育横突;指式为2-3-4-4-4(?).虽然上述特征尚不足以建立一海龙类新属种,但是仍然反映了部分海龙类单元在向海洋适应辐射的过程保留有原始爬行类的特征.这些原始特征暗示着部分海龙类可能以营陆生生活为主.
The sea dragon prehistoric fossil specimen (YIGM SPC V 0832-2) was collected from the top of the second member of the Guanling Formation of the Middle Triassic in the Triassic Piedmont, Xinzhai, Luoping County, Yunnan Province, The first discovery in the group, but also the earliest record of the long-necked sea dragon, which, although incompletely preserved, still has some unique features: the distal edges of both ends of the radius are parallel; the distal ulna is expanded; Carotid; the third metacarpal medial margin of the lateral development of transverse processes; refers to the type 2-3-4-4-4 (?) .Although the above characteristics are not enough to establish a new species of Helicobasidium, but still reflects the part of the sea dragon The unit retains the characteristics of the primitive reptiles during its adaptation to the ocean, and these primitive features imply that some of the marine dragons may dominate the terrestrial life.